The present invention relates generally to improved methods and apparatus for blood analysis, and more particularly to improved methods and apparatus for handling blood samples during a determination of the oxygen association of the blood, and charting the relation between the degree of such association and the concentration of oxygen which is in effective contact with the sample.
Normally, a chart is prepared on an instrument designed to record a series of readings representing the degree of oxygen association existing at any given oxygen concentration. The chart is used for diagnosis of clinical conditions existing in the patient by medical and/or other technicians.
According to the invention, it has been discovered that increased accuracy and reproducibility of these characteristic curves can be obtained if the blood samples are incubated or pre-treated in an atmosphere which is controlled with respect to certain variables before the samples are observed to determine the association curves.
It has also been determined that this pre-treatment or incubation can be achieved without loss of time by using the apparatus and method of the invention; specifically, while one sample is being analyzed in one portion of the analysis device, the other sample may be incubated in another portion of the analysis device. Subsequently, the just-analyzed sample is removed and a new sample is inserted in the analysis device for incubation while the just-incubated sample is being analyzed.
The novel analysis device provides a highly effective seal against atmospheric contamination, and serves to hold two samples, one each in an upper and lower slide unit, respectively. Both slides include recesses adapted to receive the analysis devices, and the upper slide also includes an aperture therein to permit exposure of the sample in the lower slide to the conditioning atmosphere within the chamber while the upper slide is in its axially innermost position. The two slides reciprocate among fully inserted, partially inserted, and withdrawn positions, thereby permitting samples to be analyzed, incubated and withdrawn, respectively.
While the general method of analysis is known, the present invention also comprehends certain improvements in the method other than those referred to above.
While the reasons for the success of the invention are not known with certainty, it is thought possible that the exposure of the blood samples to known degrees of humidity and temperature, and known concentrations of carbon dioxide tends to stabilize the blood mechanically, rendering the samples capable of more accurate analysis.
An object of the present invention is to provide an improved apparatus and method for analyzing blood samples.
Another object of the invention is to provide a blood sample analysis method which includes incubating a blood sample under controlled conditions before analyzing it for oxygen association in relation to oxygen concentration.
Still another object of the invention is to provide an analysis method wherein a series of samples are incubated, analyzed and removed, respectively, with each incubated sample being analyzed as a subsequent sample is being incubated.
Another object is to provide an apparatus which includes plural blood sample holder slides arranged for movement between positions permitting the samples to be inserted or removed, incubated or analyzed, with the slides being operable separately of each other in the sequence referred to herein.
Another object is to provide a method of analysis which includes the use of an optical analysis beam comprised of frequencies not heretofore used for this purpose.
These objects and advantages are achieved by providing a method of blood analysis which includes incubating a blood sample under controlled atmospheric conditions before analyzing it, and by providing a novel sample holder apparatus permitting samples to be so incubated before analysis.
The foregoing and other objects and advantages of the invention, including those inherent therein are achieved in practice by providing a method which includes the steps of placing a blood sample to be analyzed in a chamber wherein the atmosphere may be controlled, and permitting said sample to incubate before analysis of the degree of oxygen association thereof is made. The invention also achieves its objects by providing a novel sample holder analysis device permitting blood samples to be maintained within the controlled atmosphere chamber for incubation and analysis, respectively, with one sample being positioned for analysis while the other is positioned away from the light beam used to make the analysis, in a position for incubation. The invention also achieves improved operating advantages by using wave lengths in the light source which have not been heretofore used for this purpose.
The exact manner in which the foregoing objects and advantages are achieved in practice will become more apparent as reference is made to the following detailed description of the preferred embodiments of the invention set forth by way of example and shown in the accompanying drawings, in which light reference numbers indicate corresponding parts throughout the several figures.